A cross-sectional study of sweat-induced dermatitis during a South Indian summer: a glimpse of sweat gland-mediated cutaneous inflammation.

BACKGROUND: The role of sweat gland in inflammation has not received sufficient attention. The thermal stress during the summer months in tropical areas provides an opportunity to study the morphological patterns of inflammation produced primarily by the sweat gland.

AIM: To collect clinical data on sweat-induced dermatitis during the summer months.

METHODS: A hospital-based descriptive cross-sectional study was done during the hot and humid summer months of April to June in a tertiary care institute in Puducherry. Patients clinically diagnosed with sweat-induced dermatitis (dermatitis primarily due to retention or extravasation of sweat) were included in the study. A detailed history was taken, and clinical examination was done.

RESULTS: One hundred and fifty patients were included in the study. Various typical and atypical manifestations of sweat-induced dermatitis were seen. "Sweat dermatitis" presenting with dry, hyperpigmented, fissured "parchment"-like skin, shiny "crinkled cellophane paper"-like skin, or asymptomatic hyperpigmented macules was seen. Other atypical presentations included miliaria pustulosa with "hypopyon sign" and "linear and parallel ridge pattern" of dermatitis in patients with miliaria rubra affecting the lower neck and upper chest.

CONCLUSION: A wide spectrum of sweat-induced dermatitis was seen during the summer months in a tropical region. It reflects the role of the sweat gland in cutaneous inflammation. An increased awareness of atypical manifestations is needed.